Since the 1990s, scholars have increasingly interpreted Robert Adam’s (1728–1792) castle architecture as part of the architectural culture of the Scottish Enlightenment. In this period, fundamental changes in Scottish society — the emergence of progressive Enlightenment ideology and improvements in socio-cultural and economic life — shaped both new urban-planning solutions and a revised understanding of country-house architecture. The urban “improvements” of the Scottish Enlightenment undeniably made Scottish cities more convenient to inhabit; at the same time, historical and cultural monuments that lent these cities a distinctive character were often deemed obsolete and destroyed. Yet alongside the repudiation of the past there emerged an opposing impulse: nostalgia for earlier times and a search for national origins, expressed in literature and in the architecture of country houses, including Adam’s castle style. Scholars have proposed various explanations for its origins. A fuller understanding of its emergence, however, requires recognition of its markedly personal character: architecture of the past is mediated through the architect’s intellectual commitments and an array of referential sources. Adam’s castellated country houses are commonly divided into two phases, early and mature. The early castellated style is distinguished by architectural simplicity, austerity in facade treatment, and regular planning; Mellerstain, Wedderburn, and Caldwell are cited as representative examples. Adam’s mature castellated style is characterized by more complex architectural solutions, with greater movement and picturesque effect, while preserving regular planning principles; Culzean, Dalquharran, and Seton belong to this phase. The nature of Robert Adam’s castle style is thus double: modern country houses with regular, convenient plans are clothed in architectural forms associated with the past.